File sharing has been a feature of networked computer systems for many years. One form of file sharing is the peer-to-peer (P2P) model, where the files are stored on and served by personal computers of the users. Some P2P file sharing networks over the Internet utilize a centralized server system that controls traffic among the peer nodes (e.g., the PCs). The central server(s) maintain a central directory of the shared files on the peer nodes, which is updated as each user logs on. Using his or her own peer, a user submits search criteria at the central server, and in response, the server sends back a list of peers that have the data. Once the user selects a peer from the list, the selected peers sends the data to the user's computer. Napster™ is an example of a popular centralized P2P. Another type of P2P network operates without a central server, and instead, some of the peers operate as indexing nodes that keep track of the files stored on the peer nodes. Two examples of decentralized P2P networks include Gnutella™ and Kazaa™. A recent incarnation of P2P networks may transmit streams instead of files over the P2P network.
One disadvantage of P2P networks is that the peer nodes must download and install the same client application that enables the devices to become peer nodes. A peer running a client application of one brand of P2P network cannot search for and download files hosted on a peer running a client application from another P2P network brand. Therefore, file sharing in a P2P network is tied to the P2P software provider. Another disadvantage is that while P2P networks allow users to easily select and download files, little or no provisions are provided for enabling a user to initiate a file transfer to another user.
In recent years, filing sharing has migrated from the PC to handheld devices, such as personal digital assistants (PDAs) and cell phones. For example, file sharing has gained popularity on PDAs and cell phones that run the Palm™ operating system (OS) through the use of infrared (IR) beaming. The IR port on handled devices may be used to exchange information between any two IR-equipped devices, wirelessly. The Palm OS, for example, supports the sending of applications, and address, to do list, and memo pad items. When the receiving device receives a beam, the data is automatically stored in the corresponding application on the device. For example, sharing business card information with another device results in the information being automatically added to the other device's address book.
One disadvantage of file sharing using IR beaming is limited range because the sending and receiving devices must be within a few feet of each other for the file sharing to work. With IR beaming in particular, the two devices must be in line-of-sight before the communication can occur, and both devices must run the same software that controls the transfer, e.g., the Palm OS.
Bluetooth is a wireless personal area network (WPAN) standard that also may be used to transmit digital voice and data between devices. However, Bluetooth suffers from short range and limited bandwidth. Although Bluetooth provides a user with the advantage of being able to electronically send a file to another user when there is no network available, Bluetooth requires the user to go through the steps of setting up an ad hoc, wireless network so that the two devices can be paired.
A more recent type of file sharing allows a user of one device to instantly send, or “beam”, photos and contacts to the devices of other users that are available on the same Wi-Fi network, providing that each of the devices is running the same file sharing application. An example is a free file sharing application called Fliq™ offered by Mark/Space, Inc. for the Apple iPhone, ipod Touch, Mac, and Windows PC.
In operation, once the application is launched on a device, the application displays a list of nearby devices on the same network that are also running the application. The devices may be displayed with the nicknames their users assigned the device, e.g., “Mark's phone.” The user then chooses a person they want to send to from the list. The user then picks a contact or a photo to send, and initiates a file transfer by swiping his or her finger across the touchscreen display. The contact or photo is then sent to the device of the chosen person in real time.
DropCopy and Mobile DropCopy by 10base-t Interactive™ is another application that allows transfer of data between iPhones and Macs available on the same network. DropCopy includes a file navigation interface that displays file types the application can preview with an eye icon. To send the file, the user taps on the filename, then selects the destination for the file from a list of devices currently on the network.
Although applications such as Fliq and DropCopy have enjoyed some popularity, the applications have drawbacks. For example, one drawback is that for applications to work, the sender and his or her friends must be on the same WiFi network, and the same application must be running on all of the friend devices. If a friend moves outside the WiFi zone, no transfer is possible.
Another drawback is that the type of files that can be transferred is limited. For example, Fliq on the iPhone limits users to transferring contact cards and photos. File types, such as PDF files are currently unsupported. Although DropCopy allows a user to send any file or folder, not just address cards, photos and notes, DropCopy does not allow the user to send address cards or photos from Mobile DropCopy to a Mac. And just as with Fliq application, the user is limited to transferring files only with other DropCopy devices currently on the same network.
Another drawback of the applications is that the process of selecting which users to send a file to may be burdensome using portable devices that have very small screens, such as watches or other wrist-worn devices, which may be less than 40 mm in diameter. Scrolling through a list of available contacts or devices on such a small device, particularly in a crowded WiFi hot spot that may have many devices online, could be time consuming. Another factor to consider is that due to the form factor of small portable devices, a keyboard and button-based user interface integrated with small portable devices is neither practical nor aesthetically pleasing, which may further limit how users are selected and the devices paired.